Portland, Oregon, police reportedly refused to assist two 911 emergency calls from U.S. Immigration and Customs Enforcement (ICE) who were trapped inside their offices as violent protesters raged outside.

A cease-and-desist letter sent by The National Immigration and Customs Enforcement Council, a union representing ICE employees, was sent to Mayor Ted Wheeler, urging him to ensure police enforce the law equally and protect innocent people.

“Your current policy forbidding Portland law enforcement agencies from assisting employees of the Immigration and Customs Enforcement Agency who request law enforcement assistance while at or away from work is a violation of the United States Constitution’s Equal Protection Clause,” the letter reads.

According to the daily caller: Demonstrators, some affiliated with the domestic terrorist organization Antifa, set up a city of tents outside the ICE offices. After setting up camp, they became violent and incited violence several times.

“Every person in law enforcement knows there are few things as dangerous or as unpredictable than an angry mob,”said Chris Crane, president of the national union, WWeek reported Monday.

“No one could have responded quickly enough to protect our employees who were trapped inside this building. All of this because the Mayor of Portland has a beef with the president of the United States.”

The activists were able to get the government to shut down the Portland ICE offices June 20, but were able to return to work July 3, The Daily Caller News Foundation reported.

The Occupy ICE camp was officially shut down July 25, after more than a month of demonstrations. They infected the area so much, the mayor called it a biohazard.

“We understand that you have a difference of opinion with the current President of the United States, and some of his policies, but we fail to see why targeting the employees of ICE and leaving them vulnerable to violence, harassment and even death furthers a legitimate government interest,” their lawyer, Sean Riddell, says in the letter.

“Your policy has created a zone of terror and lawlessness.”

“We ask that you end your policy of not responding to calls for police services from ICE employees immediately,” the ICE union pleads in the letter to the mayor. “We would like to avoid federal litigation, but we are prepared to protect our membership and their families.”